The invention relates generally to control systems, and more particularly to a digital control data processing and display method and apparatus which verifies symbol positioning accuracy by receiving the positioning of a blue pixel on an LCD or other pixelated display, computing derived input information based on detected symbol position and symbol type and comprising the desired input information to the actual input information.
Conventionally, methods and apparatus for verifying the operational status of digital control systems, specifically for flight guidance applications, have been used. For example, there have been known control system apparatuses which project a display symbol in the form of a light image that conveys information concerning the status of an operational state of the system. Such display symbols include pointers and other characters whose position on or direction of movement across the display screen conveys to the observer information about a particular operational state.
Further, a conventional apparatus for determining whether a display symbol conveys the correct information includes the use of a test program which is executed while the control system is off-line. The test program applies known input information to the data processing apparatus which produces output command information in accordance with a known operational control function. A display symbol generator responds to the output command information by projecting a preassigned pointer symbol at a known location on the display screen. A photo detector positioned at the known location receives the light emitted from the pointer symbol and thereby acknowledges the nominal performance of the control system after a successful execution of the test program.
These methods of verifying the operational status of the control data processing and display system are capable of neither verifying the status of the system in real time operation nor providing an adequate test for detecting latent software design defects which arise during the execution of a particular control operational function.
Thus, there is a need for a symbol position and location monitoring system which may be used during flight operations.
It would be desirable to provide a system and/or method that provides one or more of these or other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments which fall within the scope of the appended claims, regardless of whether they accomplish one or more of the aforementioned needs.